Yellow/brown leaves, dying branches on Cleveland Select Pear tree - Ask Extension
We have a 6-year-old Cleveland Select pear tree whose leaves have been turning more yellow brown for the last few summers. It is flowering less in th...
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Yellow/brown leaves, dying branches on Cleveland Select Pear tree #807473
Asked August 22, 2022, 1:53 PM EDT
We have a 6-year-old Cleveland Select pear tree whose leaves have been turning more yellow brown for the last few summers. It is flowering less in the Spring and the leaves seem to be turning yellow and then brown, working from the top of the tree down. (A few years ago, this was happening just at the top tips of a few branches, but is becoming more widespread. This summer, my husband trimmed out several branch sections that appeared to be dead. The trunk seems healthy, and we do not see any signs of root curling/girdling. Any ideas?
Larimer County Colorado
Expert Response
Hi Stephanie,
The yellowing is called chlorosis and the definition is yellow leaves with green veins. There are many causes, including the pH of the soil and the tree's inability to take up iron in the form available at a higher pH, wet soils, salty soils, and compaction. It can also be caused by roots not functioning properly.
In this case, since callery pear generally don't get chlorosis due to pH issues, I suspect it's because of a root issue or watering.
It looks like you pulled back some of the mulch around the trunk. What we would like to see is a prominent root flare (where the trunk flares out at the base). Not seeing this could be because the tree was planted too deep and the first roots are below the soil grade. Because roots need oxygen to function properly, if the roots are too deep, it could affect root function. It may also be due to a circling or girdling root.
I would encourage you to pull back the mulch and see where the trunk flare begins. If you are able to carefully remove soil to expose the flare, you can do that. But don't do excessive things without the consult or lead of a certified arborist.
If the tree is on drip irrigation, check the moisture levels too. While the photo looks dark, it's hard to tell if it's also wet.
You can find a certified arborist to assist you going forward at http://www.treesaregood.com
The yellowing is called chlorosis and the definition is yellow leaves with green veins. There are many causes, including the pH of the soil and the tree's inability to take up iron in the form available at a higher pH, wet soils, salty soils, and compaction. It can also be caused by roots not functioning properly.
In this case, since callery pear generally don't get chlorosis due to pH issues, I suspect it's because of a root issue or watering.
It looks like you pulled back some of the mulch around the trunk. What we would like to see is a prominent root flare (where the trunk flares out at the base). Not seeing this could be because the tree was planted too deep and the first roots are below the soil grade. Because roots need oxygen to function properly, if the roots are too deep, it could affect root function. It may also be due to a circling or girdling root.
I would encourage you to pull back the mulch and see where the trunk flare begins. If you are able to carefully remove soil to expose the flare, you can do that. But don't do excessive things without the consult or lead of a certified arborist.
If the tree is on drip irrigation, check the moisture levels too. While the photo looks dark, it's hard to tell if it's also wet.
You can find a certified arborist to assist you going forward at http://www.treesaregood.com
